1. Field of the Invention
The present disclosure relates to methods for preparing hydrochloric acid from hydrogen gas and chlorine gas.
2. Description of the Relevant Art
Chorine gas and caustics such as alkali metal hydroxides are typically produced in a commercial setting through the electrolysis of, for example, alkali metal halides. For example, caustics such as sodium hydroxide and potassium hydroxide may be produced on a commercial scale through the electrolysis of sodium chloride and potassium chloride, respectively. In diaphragm cells that utilize semi-permeable cation exchange membranes, aqueous sodium chloride may be provided to the area of the anode, which is separated by the membrane from a cathode. As sodium ions cross the membrane, the chloride ions oxidize at the anode to form chlorine gas, and water is reduced at the anode to form hydrogen and hydroxide ions. While the hydrogen ions combine to form hydrogen gas, the hydroxide ions and sodium ions combine to form NaOH, resulting in the net production of a NaOH solution, H2, and Cl2.
Although the commercial production described above typically results in caustic solutions that are suitable for direct use, H2 and Cl2 byproducts present certain challenges in terms of disposal, particularly given the reactive nature of those byproducts. In some instances, H2 and Cl2 may be recombined to form HCl, which can be used as a gas or absorbed into water to form an aqueous solution. However, the high temperatures and pressures typically associated with the processing of H2 and Cl2 can yield highly unstable conditions that result in the combustion and/or explosion of the reactants.
Therefore, there exists a need to develop methods that safely and effectively removes the H2 and Cl2 gases from certain commercial processes, or in the alternative, combines H2 and Cl2 to form HCl for other industrial applications.